Why would there be a Fairy AND a Light type? That makes absolutely no sense, haha. And yeah, Genesect can transform into this flying car thing. And where are you guys getting these rumors from? Hard to be credible with not even a vague source....

Most of these rumors have either been floating around sites like Pokébeach, or they popped up on 4Chan and have been making the rounds since then. Most of them have already been debunked though by the creators of them (like Mr. XY from 4chan for example), so at this point it's just taking things with a grain of salt =P

I don't think there would be both a Fairy AND a Light type. I feel like people have been using them pretty interchangeably as far as the new type comes, as they're mildly similar in regards in what they'd be there to accomplish. So no, I doubt there would be both.